I can't speak on whether or not it's the "time to buy", and don't know a lot about Franklinton (although it seems there are a lot of people on CU working hard to improve the area.) But I can tell you a little about my thoughts/experience in WP.
One of the things I love about WP is its proximity to the Short North and campus. No matter what, this isn't going to change. When I look at a slightly bigger picture, I take comfort in knowing that I'm not necessarily waiting on the area to take shape. I only have to walk 2-3 blocks and I'm strolling past new development (MiddleWest spirits, Smith & High, American Apparel *fingers crossed on the new Kroger).
1 more block south and I'm walking by antique stores and coffee shops in the Short North. A couple blocks north and I'm catching a movie at the Gateway and beers at MadMex.
Hop on a bike and you're having brunch at Surly Girl in 2-3 minutes. If I decide to stay out late it only costs a few bucks for a cab ride from anywhere in the SN.
I feel in WP, it's more just waiting on a great area to fill in completely. The fact that there is so much development slated deeper in Weinland Park (Coated Fabrics site, Auld factory, etc.) is a huge step in
jump-starting the rest of the neighborhood. But it's nice to know that no matter what happens you are already a short walk from such a developed area.
As far as my personal experience, I have to admit at first I was a little apprehensive about the neighborhood. I was definitely a little nervous on my first few walks to the SN. However I've gradually made conversation with the familiar faces along the way and people have been very friendly. I now look forward to the walks just to say hi.
I'll also say that doing a few favors for your neighbors does wonders. I was pretty nervous moving in. Sketchy carryout on the corner, pretty run-down houses with people hanging out all around. I made an effort to cut some of their weeds- fix a bike- repair a broken security light. In turn I've gained a bit of a neighborhood watch crew as well as neighbors that wave and say hello each day ( which is a lot more than I had in the Short North.) and even an occasional free 6 pack.
I'm sure the same holds true in Franklinton. While there is definitely a fair share of rif-raff, there are also a lot of long time residents that welcome you and positive change to the neighborhood.
Best of luck in the house hunt- PM me if you want to know more about my experience thus far!